Penny Blood: Serial Sensation and Working-Class Entertainment — page 36: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

cH. 11.) CONDITION OF INTERIOR. 19 1. Maskelyne, 1775, by means of the deflection of the plumb-line by the mountain Schehallion determined the mean density of the earth at 5:0. 2. Cavendish, 1798, by the torsion rod and two Jeaden balls as attracting masses, weighing together 700 pounds, in 23 ex- periments determined the mean density at 5°448. 3. Reich, 1837, using one large leaden ball of 99 pounds for the attracting mass, in 57 experiments determined the mean density at 5°44, 4. Baily, 1842, using two large leaden balls, each weighing 3803 pounds, in 2004 experiments determined the mean density at 5°67. 5. Airy, 1856, by experiments with the pendulum in Harton Colliery, at a depth of 1260 feet, determined the mean density of the earth at 6°566. The mean density of the ordi- nary beds of rock above was determined by W. H. Miller at 2°56, and of the coaly beds at 1°43. Airy considered that his determination may “ compete with the others on at least equal terms.” 6. Col. James, 1856, by observations on the deflection of the plumb-line at Arthur's Seat determined the mean density of the earth at 5°316. The mean density of the rocks at Arthur’s Seat was determined at 2°75. 7. Mallet estimates the weight of a cubic foot of granite at 178°34 pounds, which makes its density 2°69. 8. Waltershausen finds the specific gravity (or density) of Albite......cccccececees 2°53 Limestone ............ 2°63 Mica ...ccscccccocceee 2°92 Mean ......csecceeee 2°66 which he takes as the mean density of surface rock. Such a mean, however, would require these minerals to occur in equal proportions in the rock. We have then for the mean densities according to the ex- periments respectively of 2—2 GONG oOo SS (CO)